1. Field of the Invention
This invention pertains to the field of treatment of gastro-esophageal reflux disease (GERD). More specifically, this invention pertains to a method and apparatus for treating of GERD by lengthening an esophagus.
2. Description of the Prior Art
A. GERD
Gastro-esophageal reflux is a physical condition in which stomach acids reflux, or flow back from the stomach into the esophagus. Frequent reflux episodes may result in a more severe problem known as gastro-esophageal reflux disease (GERD). GERD is the most common form of dyspepsia, being present in approximately 40% of adults in the United States on an intermittent basis and some 10% on a daily basis as described in U.S. Pat. No. 6,098,629 Johnson et al., dated Aug. 8, 2000.
As indicated in Johnson et al., heartburn is defined as a burning sensation or discomfort behind the breastbone or sternum and is the most common symptom of GERD. Other symptoms of GERD include dysphasia, odynophagia, hemorrhage, water brash and pulmonary manifestations such as asthma, coughing, or intermittent wheezing due to acid aspiration.
GERD is generally considered to be the result of a motility disorder which permits the abnormal and prolonged exposure of the esophageal lumen to acidic gastric contents. Hunt, “The Relationship between the Control of pH and Healing and Symptom Relief in Gastro-Oesophageal Reflux Disease”, Ailment Pharmacol Ther., 9 (Suppl. 1) pp. 3–7 (1995). Many factors are believed to contribute to the onset of GERD. These include transient lower esophageal sphincter (LES) relaxations, decreased LES resting tone, delayed stomach emptying and an ineffective esophageal clearance.
B. GERD Treatments
A summary of a number of GERD treatments can be found in DeVault, et al., “Updated Guidelines for the Diagnosis and Treatment of Gastroesophageal Reflux Disease”, Amer. J. of Gastroenterology, Vol. 94, No. 6, pp. 1434–1442 (1999). The elusive nature and complexity of GERD is evidenced by the numerous attempts and suggestions for treatment and the continuing need for treatment techniques.
a. Lifestyle Changes
Treatments for GERD include lifestyle changes such as weight loss, avoidance of certain foods (e.g., coffee, caffeine, alcohol, chocolate) that exacerbate the symptoms of GERD and avoidance of excessive bending. Elevation of the head of a patient's bed helps prevent nocturnal reflex. While these avoidance strategies may be helpful, there is relatively little data pointing to the efficacy of lifestyle modification for the treatment of GERD.
b. Medicine
Certain medications used for treatment of GERD have been administered for years with varying success. Conventional antacids such as Tums® and Rolaids® may, in some patients, produce short-term relief but often have side effects including diarrhea and constipation.
Other drugs have been more effective at controlling GERD, but fail to treat underlying causes of the disease and have been proven to be extremely expensive and not readily available to all patients due to such expense. Examples of such drugs are H2-receptor antagonists (which control gastric acid secretion in the basal state) and proton pump inhibitors (which control meal-stimulated acid secretion). Hunt, supra. Both classes of drugs can raise intragastric pH to about 4 for varying durations. Hunt, supra.
c. Surgery
A. Fundoplication
A traditional surgical treatments for GERD is fundoplication. Normally performed as an open surgical approach, fundoplication includes wrapping an upper portion of the stomach (the fundus) around a lower portion of the esophagus in the region of the LES.
The region of the esophagus near the LES junction is commonly referred to as the Z-line. At this location, the tissue of the esophagus merges with the tissue of the stomach. Commonly, this location is below the diaphragm of the patient. However, in some patients, this location may reside above the esophageal hiatus (the opening in the diaphragm through which the esophagus passes) requiring surgery in the thoracic cavity of the patient. Also, this location is in close proximity to vital structures such as nerves and blood vessels.
Fundoplication can treat GERD effectively in many patients for a period of time. In most cases, the patient returns to drug treatment after a length of time following surgery. Further, the surgery includes risks and common side affects of heartburn, dysphagia and gas bloat. Laparoscopic procedures for treatment of GERD include those disclosed in U.S. Pat. No. 5,403,326 to Harrison et al. dated Apr. 4, 1995. Laparoscopic procedures are complicated by close proximity to vessels and nerves as described above. Endoscopic procedures are also known which cinch and suture tissue of the esophagus An example of an endoscopic product is the EndoCinch™ system of C.R. Bard company.
Surgical procedures suffer from a high complication rate. Commonly. Surgical patients revert to a continuing need for drug therapy. Lafullarde, et al., “Laparoscopic Nissen Fundoplication: Five-Year Results And Beyond”, Arch. Surg., pp. 180–184 (2001); Hinder, et al., “Laparoscopic Nissen Fundoplication Is an Effective Treatment for Gastroesophageal Reflux Disease”, Ann. Surg., pp. 472–483 (1994); Perdikis, et al., “Laparoscopic Nissen Fundoplication: Where Do We Stand?”, Surg. Laparosc. Endosc., pp. 17–21 (1997); and Rantanen, et al., “The Long Term Results of Open Antireflux Surgery in a Community-Based Health Care Center”, Am. J. Gastroenterol., pp. 1777–1781 (1999).
B. LES Bulking
Less invasive surgical treatments for GERD and include techniques for bulking the lower esophageal sphincter. Such a technique is described in U.S. Pat. No. 6,098,629 Johnson et al, Aug. 8, 2000. Johnson et al. discloses bulking through an injected polymer in the esophagus. A polymer injection is the basis of the Enteryx™ and Gatekeeper™ systems of the Boston Scientific and Medtronic companies, respectively. Supporting the LES through radiofrequency induced scarring is the basis of the Strettar™ system of the Curon company.
C. LES Banding
Surgical techniques for the treatment of GERD have also included placement of restriction devices around the esophagus in attempts to compensate for an incompetent lower esophageal sphincter (LES). An example of such is shown in U.S. Pat. No. 5,919,233 to Knoph et al dated Jul. 6, 1999, and U.S. Pat. No. 5,006,106 to Angelchik dated Apr. 9, 1991. The devices of the '233 and '106 patents are restrictions placed around the esophagus at the location of the incompetent LES. Such devices may slip during use. Further, such devices have a problem of requiring dissection around the LES junction. Crookes, et al., “The Angelchik Prosthesis: What Have We Learned in Fifteen Years?”, Ann. Thorac. Surg., pp. 1385–1386 (1994); Evans et al., “An Objective Long-Term Evaluation of the Angelchik Antireflux Prosthesis”, Annals of the Royal Colege of Surgeons of England, pp. 355–360 (1991); and Kozarek et al., “An Anti-Reflux Prosthesis in the Treatment of Gastroesophageal Reflux”, Annals of Internal Medicine, pp. 310–315 (1983).
Other suggested treatments include placement of an adjustable band around the esophagus. These are shown in U.S. Pat. No. 6,450,173 to Forsell and U.S. Pat. No. 6,432,040 to Meah dated Aug. 13, 2002.
D. Pacing
Other suggested treatment techniques include placement of pacemakers for stimulating muscle contractions in the esophageal sphincter, the stomach muscles or in the pyloric valve. U.S. Pat. No. 6,104,955 to Bourgeois dated Aug. 15, 2000 and U.S. Pat. No. 5,861,014 to Familoni dated Jan. 19, 1999.
E. Esophageal Lengthening
Surgical treatment has also included the Collis-Nissen gastroplasty for patients with short esophagus. Mattar, et al., “Short-Term Outcome of Collis-Nissen Gastroplasty Using a Wedge Gastroplasty Technique”, Abstract No. M1910, Digestive Disease Week (DDW) (Joint meeting of Amer. Assoc. for the Study of Liver Diseases, Amer. Gastroenterological Assoc., Amer. Soc. For Gastrointestinal Endoscopy, Soc. For Surg. Of the Alimentary Tract) (May 17–22, 2003). In the Collis-Nissen gastroplasty, a portion of the stomach is removed to lengthen a foreshortened esophagus by approximately 3–4 centimeters. This creates an extended esophageal portion (referred to as a neo-esophagus) and has resulted in a reduction of GERD in some patients.
F. Obesity Treatments
From time-to-time, obesity treatments have demonstrated an impact on GERD. Such treatments include placement of bands (referred to as LAP bands) around the stomach. An example of a LAP band is shown in U.S. Pat. No. 5,266,429 to Kuzmak dated Jul. 13, 1993. LAP bands and other gastric bandings are disclosed in Schauer, et al, “Surgical Management of Gastroesophageal Reflux Disease in Obese Patients”, Seminars in Laparoscopic Surgery, Volume 8, Number 4, pages 256–264 (2001). Such LAP bands wrap around a portion of the fundus to create a greatly reduced volume portion of a fundus above the LAP band. Such bands create an upper chamber above the band to create a sensation of satiation after consuming only a small volume of food. See also, U.S. Pat. No. 5,549,621 to Bessler et al., dated Aug. 27, 1996; U.S. Pat. No. 5,226,429 to Kuzmak dated Jul. 13, 1993; and U.S. Pat. No. 4,592,339 to Kuzmak et al. dated Jun. 3, 1986.
Notwithstanding multiple attempts at various types of treatment, GERD continues to be a serious disease proving to be difficult to treat by any of the foregoing prior art techniques. In view of the foregoing and notwithstanding various efforts exemplified in the prior art, there remains a need for an effective treatment for GERD. It is an object of the present invention to provide a novel treatment and novel apparatus for the treatment of GERD.